<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script>
    //document.write("123")


    //隐式丢失
    /*var write = document.write;
    write("123")*/

    //使用显示调用来解决
    var write = document.write;
    write.call(document,"123")

</script>
</html>